Effect of quadric shear basic zonal flows and topography on baroclinic instability

Xiujie Zhang; Hongxin Zhang; Yuying Yang; Jian Song

doi:10.1080/16000870.2020.1843330

Effect of quadric shear basic zonal flows and topography on baroclinic instability

Tellus

Volume 72 (2020): Issue 1

By: Xiujie Zhang, Hongxin Zhang, Yuying Yang and Jian Song

Open Access

|Jan 2020

Abstract

On the β plane approximation, the two-layer quasigeostrophic mode is used to study the baroclinic instability of the quadric shear basic zonal flows on a uniform bottom topography. The phase speed and growth rate of instability waves are functions of the shear zonal basic flows and bottom topographic slope. The study focus is on the effects of topography and the quadric shear basic zonal flows (the second derivative of basic zonal flows is not zero). The meridional slope destabilise (stabilise) zonal flows, it plays an unstable role in disturbance, moreover the effect of the second derivative of basic zonal flows is to accelerate the instability of disturbance. The zonal slope always destabilises the zonal basic flows through zonal and meridional wavenumber. Moreover, the effect of the second derivative of basic zonal flows is to accelerate the instability of disturbance.

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Articles in this issue

DOI: https://doi.org/10.1080/16000870.2020.1843330 | Journal eISSN: 3035-9554

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Language: English

Page range: 1843330 - 1843330

Published on: Jan 1, 2020

Published by: Stockholm University Press

In partnership with: Paradigm Publishing Services

Keywords:

topographic slope,

basic zonal flows,

quadric shear,

baroclinic instability,

β plane approximation

© 2020 Xiujie Zhang, Hongxin Zhang, Yuying Yang, Jian Song, published by Stockholm University Press
This work is licensed under the Creative Commons Attribution 4.0 License.

Volume 72 (2020): Issue 1